Pretoria - A pregnant rhino cow has died under mysterious circumstances on the farm neighbouring that of Dawie Groenewald, the suspected mastermind of an alleged rhino poaching syndicate who was arrested last week.

Lourens Louw, owner of the farm Mafunyani, in the Messina district, confirmed on Tuesday that one of his rhino cows died on Monday.

Beeld has learned that the police are conducting tests on a poisonous substance found near a watering hole on the farm.

Mafunyani borders on the farm Prachtig, which belongs to 42-year-old Groenewald, a well-known figure in wildlife circles.

Groenewald, a former policeman, was released on R1m bail in the Messina magistrate's court last week in connection with his alleged involvement in a syndicate that kills rhinos.

Louw was not able to say on Tuesday what had caused the rhino cow's death. According to him, it doesn't look like the animal was shot.

"At the moment I don't know whether the animal might have been poisoned or shot. I'm waiting for the result of the police investigation."

Young cow

According to him the rhino cow - who was about 4 years old - was pregnant.

"It's possible that she died when she had to give birth. She had a lot of blood on her."

Louw said the animal's horns had not been sawn off. After the animal died, police cut the horn off and are holding it in safekeeping.

"We'll have to wait for the post-mortem to tell us what killed her."

Louw denied rumours that he gave any information regarding Groenewald's alleged involvement in rhino killing to the police or game wardens.

Meanwhile, Sarel van der Walt reports that farmers with rhinos have been warned to be on the look-out for poisoned cabbages which are placed in rhinos' "territorial dung heaps".

Wildlife Ranching South Africa (WRSA) released a statement calling on game farmers to contact the police as soon as possible if they spot any of these poisoned cabbages.

Rhinos have the habit of visiting their dung heaps often, and then eat whatever food has been planted there.

The organisation also warned farmers to be very cautious, since the chances are great that poachers are still in the area.